110064041

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7/30/2019 110064041 http://slidepdf.com/reader/full/110064041 1/5 T he three paring chisels, center, are lightweight tools shaped fo r precise work in tight places. The firmer chisel, left, is heavier overall, without side bevels, to resist the shock of hammering. The Stanley chisel, right, is an intermediate design for general work. O ne of my favorite, and often enjoyed, times is the first slice I take with a paring chisel after a good sharpening. This most basic and useful tool is also the most versatile, doubling as a plane, a drawknife, even a cabinet scraper. But like any tool, it only performs for the hands that understand its basic personality quirks and all. There are many types of chisels, from the brutal timber framers' mortiser down to the tiniest carver, each one requiring a differ- ent technique. Here, I'll limit myself to an examination of the parer and how it's used for fine cuts. You can pare with any chisel, so much of the advice here will apply to all chisels. But the parer is a special case in that it is a lightweight, specially shaped tool that can get into places other chisels can't. Paring chisels are thin and light, with beveled edges to reduce weight and increase maneuverability. They are not expected to take hammering or prying. The nature of this tool is to remove light shavings of wood, usually with a finished surface as the intended result: sides of dovetails, tenon shoulders, etc. The plane finishes large surfaces, the paring chisel finishes small ones. Incorrect use of a tool that's not necessarily intended for finish cuts—a drawknife for example—results in temporary frustration and extra work. Incorrect use of a paring chisel results in poor joints and ten years of irritation from having to look at them across the living room.  Any discussion has got to beg in with the usual enjoinder: buy the best. There's no point in trying to master a second-rate tool. But don't fret, I'm not suggesting that you buy a drawerful of expensive chisels. You can get by with two or three good parers, say, in., in., and 1 in. or 1 in. You have many years to fill up that drawer. For rough-cut pounding, also pick up a couple of solid, inexpensive hooped socket or reinforced plastic-handled butt chisels. I like Stanley. There's no need to break the bank.  As I'll discuss further along, the action of paring—whatever sort of chisel you may be using—requires that the flat chisel back be used to "jig" the cutting edge in a straight line. It follows that the longer the blade, the longer the controlled cut. While this is true, it's also true that sometimes smaller areas need to be pared, and a long tool gets in the way. . . hmmm. . .what to do? Long- bladed patternmakers' chisels are really great for big work, and I go one step further and use cranked-handled ones—tools in which the shank of the chisel is bent so that the line of the handle is parallel with, but above, the line of the blade. "With these, you can pare down a bung in the center of a sheet of plywood, if you really care to. But since these tools are extraordinarily expensive (not to mention hard to find), go for an average-length bench chisel, and it will take care of 90% of your needs. It would be simple to describe some ideal working grip and, thence, the perfect handle for a paring chisel. You would then take it in hand, step up to the bench and find that the job you're doing is not ideal, and you'd end up with an entirely different grip and the shape of the handle would then be irrelevant, if it  wasn't actually inconvenient. Better a plain handle that will give

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Page 1: 110064041

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The  three paring  chisels, center, are lightweight  tools shaped fo r precise work  in tight places. The firmer chisel, l e f t , is  heavier overall,without side bevels, to resist the shock of hammering. The Stanley chisel, right, is an intermediate design for general work.

One of my favorite, and often enjoyed, times is the first

slice I take with a paring chisel after a good sharpening.

This most basic and useful tool is also the most versatile,

doubling as a plane, a drawknife, even a cabinet scraper. But like

any tool, it only performs for the hands that understand its basic

personality quirk s and all.

There are many types of chisels, from the brutal timber framers'

mortiser down to the tiniest carver, each one requiring a differ-

ent technique. Here, I'll limit myself to an examination of the

parer and how it's used for fine cuts. You can pare with any 

chisel, so much of the advice here will apply to all chisels. But

the parer is a special case in that it is a lightweight, specially 

shaped tool that can get into places other chisels can't. Paring

chisels are thin and light, with beveled edges to reduce weight

and increase maneuverability. They are not expected to take

hammering or prying. The nature of this tool is to remove light

shavings of wood, usually with a finished surface as the intended

result: sides of dovetails, tenon shoulders, etc.

The plane finishes large surfaces, the paring chisel finishes

small ones. Incorrect use of a tool that's not necessarily intended

for finish cuts—a drawknife for example—results in temporary 

frustration and extra work. Incorrect use of a paring chisel results

in poor joints and ten years of irritation from having to look at

them across the living room.

 Any discu ssio n has got to beg in with the usual enjo inde r: buy 

the best. There's no point in trying to master a second-rate tool.

But don't fret, I'm not suggesting that you buy a drawerful of 

expensive chisels. You can get by with two or three good parers,

say, in., in., and 1 in. or 1 in. You have many years to fill up

that drawer. For rough-cut pounding, also pick up a couple of 

solid, inexpensive hooped socket or reinforced plastic-handled

butt chisels. I like Stanley. There's no need to break the bank.

 As I'l l discuss fur ther along, the action of paring—whatever

sort of chisel you may be using—requires that the flat chisel back

be used to "jig" the cutting edge in a straight line. It follows that

the longer the blade, the longer the controlled cut. While this is

true, it's also true that sometimes smaller areas need to be pared,

and a long tool gets in the way. . . hmmm. . .what to do? Long-

bladed patternmakers' chisels are really great for big work, and I

go one step further and use cranked-handled ones—tools in which

the shank of the chisel is bent so that the line of the handle is

parallel with, but above, the line of the blade. "With these, you can

pare down a bung in the center of a sheet of plywood, if you

really care to. But since these tools are extraordinarily expensive

(not to mention hard to find), go for an average-length bench

chisel, and it will take care of 90% of your needs.

It would be simple to describe some ideal working grip and,

thence, the perfect handle for a paring chisel. You would then

take it in hand, step up to the bench and find that the job you're

doing is not ideal, and you'd end up with an entirely different

grip and the shape of the handle would then be irrelevant, if it

 wasn 't actu ally inconveni ent . Better a plai n handle that wil l give

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 A mortising chisel, top, cannot get into tight corners because of its square sides; the paring chisel, above,has no problem because of its side bevels, which can be ground to al-most a knife edge. Taking this thought one step further, the author modified a small parer's cutting edge to form a double-skew chisel, right,

 for slicing into dovetail corners. In all these cases, the right hand powers the 

cut, while  the  left  rests  against  the work and grips the tool for control.

When paring a straight  line, such as  this  teshoulder, the  left  hand  backs  up the  toolcontrol, while the right hand pivots the cutedge  down. With a  series of  cuts  (see drawithe flat back of the chisel can jig itself alonglength of the shoulder that has already bcut, as well as along the scribed shoulder li

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the versatility of grip so necessary to a proper job. The simple

oval handles on Marples or Sorby tools are great, even thoughthe smaller sizes may need a flat spot planed on one side of the

handle to keep them from rolling off a not-so-level tabletop. A very im po rtan t det ail is the fi ni sh in g of the sur face s of the

tool. It is imperative that the back of the chisel be ground flat,

not belt sanded! This is easy to check if you're buying off the

rack: just grab a steel ruler and hold it against the surface. You

don't want to see light between the two. If you're catalog-buying

and they send you a dud, send it back. It's the only way that

manufacturers and distributors will ever get the picture.

 As men tio ned earl ier, paring chis els have beveled side edges,

and the care with which this is done is an indication of the overallconcern the manufacturer has for the product. The maneuverability 

that side beveling gives you is apparent when working into an

acute angle, such as next to a dovetail, as shown in the top

photos on the facing page. You can re-grind this bevel almost to

a knife-edge. To carry this idea a litt le further , I modi fied a -in.

bench chisel (shown in the large photo, p. 42) and made, ineffect, a two-edged skew. Thus, I get a slicing cut (on either

side), even when I push the blade in a straight line.

Now, I'm sure that you've already muttered something aboutmy remarks that paring chisels are not for hammering on. I

know, I know. . . I hammer on them, too, occasionally. But only 

 wit h a wooden ma llet , and then only light ly. Besides , par ing is,by definition, done just with the hands. Blasting away with amallet on a heavy mortising chisel doesn't permit the intimacy 

that develops between your hands and a paring chisel during a

long day of cutting joints. Like a tiny stone in your shoe, a sharp

edge or protruding piece of hardware can become a real irritant to

 your hand in a short tim e—w hich is another reason for choos ing

smooth handles (i.e. no butt hoops).

Manufacturers usually leave sharp corners where the body of 

the blade tapers back to form the shank. I grind these trailing

corners off the blade to avoid opening up a finger if my sweaty 

palm slips, and I file any proudness off the edge of the ferrule,

 which idea lly sh ould be fl ush wi th the wood of th e ha nd le . Thi s

 wan ts to be as com fy as an old loaf er.

Now, before you can really understand the proper use of a

paring chisel, you have to appreciate a key concept.

 Ask yoursel f what would happen if you stuck a coil spring on

the handle and held it  while trying to take a shaving off animportant piece of work. Why, as soon as you got near the end of 

the cut, the spring would unload, the chisel would jump andmake a mess of everything in its way. You would have no control.

Unfortunately, this can happen any time you go to work. Themuscles and tendons in your hands and arms will act just like the

spring unless you develop proper paring technique. There are

Bahco's ergonomic chise l   by Sandor Nagyszalanczy 

I always thought that chisels were all aboutthe same: a little fancier handle here, a littleharder tool steel there. But my nonchalancewas put to the test recen tly when I tried achisel created by design methods usually re-served for jet cockpits and auto interiors.Made by one of the world's leading toolmanufacturers, Bahco of Sweden, the Ergo

line of hand tools is inspired by modernmethods of ergonomics, or "human factorsengineering." Bahco's aim was a chisel thatwould reduce hand and wrist fatig ue whileminimizing the risk of injury, common inhand-labor-intensive work.

Conny Jansson, director of R&D at Bahco,and a team of consultants began by videotap-ing woodworkers on the job and analyzingtheir individual physical movements. They also used computerized measuring devicesattached to both people and mannequin-type figures to study worker functions andmeasure stress.

The collected data provided design cri-teria for the improvements incorporated in

the Ergo chisel: a longer, textured handlelarge enough to accommodate two hands; agently rounded, knob-like end to reducepalm pressure and protect the fingerswhen struck by a mal let ; a smo oth blade-to-handle transition to allow a closer gripfor delicate work; and a shorter, stiff blade—angled in relation to the handle—for a higher angle of relief when workingin close on flat surfaces.

I was impressed by the scientific treat-ment, but wondered if all the high-tech wasworth it. To find out if the Bahco performedlike a European sports car, I gave it a road

Sleek as a Swedish Saab, the Ergo chisel is as much a product of science as it is art.

test around the shop. The overall heft andfeel of the chisel was gratifying. There wasno feeling of cheapness, and the oval shapeof the molded polypropylene handle gave agood sense of blade position relative tograsp. Since I have large hands, I appreciatedits generous size, although I could only usethe palm of my other hand on the chisel'sbutt end. I used it with a mallet and the han-dle felt very positive when struck; evidently,

it won't mushroom over time. The socket-style attachment and angle of the blade gavethe tool a feel similar to Japanese chisels I've worked wit h. At a claimed Rockwell hard-ness of 58 to 60, the blade sharpened andhoned well and held an edge even afterbeing pounded into dense rosewood.

I didn't much like the surface of the Ergo'shandle. Despite the groove textured surface,the black plastic was just a little too slick formy taste. Also, an indented area on the chisel'shandle where Bahco molds in its trademark

 was uncomfortable to grasp, nearly negat ing,for the sake of product identity, all the

effort that went into making the tool's handfit revolutionary.

So, is ergonomics a gimmick or a giantstep in the evolution of hand tools? Al-though I usually choose a tool for the way itperforms, I'd be drawn to Ergo's high-techmodern appearance, even if I knew nothingabout all the computer-aided effort that

 went into its design . Bahco has created ahigh-quality tool that's got more going for it

than a trendy design, but I can't say I'mready to throw out all my antiquated chiselsjust yet; I still prefer the feel of a wood han-dle over plastic. If you're comfortable withthe tool, you may not be with the price—$15 for the 1-in model. But all that intelli-gent Swedish design—whether it's for handtools or Saabs—doesn't come cheap.

Sandor Nagyszalanczy is an assistant edi-tor for  Fine Woodworking. Bahco's  Ergochisels are available from Woodcraft Sup-

 ply, Woodworker's Supply of New Mexi coand Garrett Wade.

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Successful paring dem ands forward pressure to make the cut and firm control   to keep it in line. At top l e f t , th e  controlling hand, the  l e f t , also acts  as a  brake  so the  chisel  will  not spring 

 fo rw ar d un co nt ro ll abl y an d ch ip ou t th e woo d at th e f ar en d of the workpiece. Below that is a practical one-handed grip—the heel of the han d acts as a fulcrum; the right thum b arcs the chis-

el like a lever through the w ood, slicing through th e wood fibers.Control in paring comes easily when large muscles of the body are used to drive the tool. Shown above is one of the most com-mon techniques: Podmaniczky uses his chin a gainst his fist and the end of the  handle, with  th e  l e f t   hand  helping  to keep th e  tool on line. Other strategies include pushing with hip or chest.

two ways to overcome this problem: dampen the spring action,

or substitute inertia of body mass for muscle power.In most cases where I use my right hand to power the cut, I

use my left hand to help guide the cut and restrain the cuttingaction. By squeezing the blade and resting part of my left hand

against the work—sometimes the forefinger, other times the heel

of my hand or whatever is convenient—I have real control and

can stop the cut whenever I want, right on a dime. As Imentioned earlier, the back/side edge of any chisel has to bekept in good condition—actually sharp—so that there is a slightdanger with this grip that you'll begin taking little slices off your

finger. Try to apply the gripping pressure in the middle of the

blade and you can avoid irritation.

 As shown above, when I'm at the bench cutting straight down,I use my head. Despite what my wife occasionally thinks my 

head is full of, it is quite heavy, and my chin can really move that

chisel. The idea is to keep the butt inside the fist so that the chin

pushes against soft meat. In practice, the handle creeps out, but you put up with it because it gives a bit more control .

 A vari ation on this theme is to grab the chis el anywhere along

its length and use the chin to push against the side of the handleand forefinger. Both these strategies eliminate the problematic

springiness of arm muscles. You can use your hip, chest or other

parts of your body in this manner, depending on the circumstances.

Once in a great while, you'll look a bit foolish with one leg upon the bench in order to get the right angle, but you gotta do

 what you gotta do. A plane is a jig that holds a "chisel" and forces it to cut in a

straight line by virtue of a long flat sole. Without this jig, keeping

the cutting edge going in a straight line is a bit harder, but as I

mentioned earlier, you still have a way to partially jig the action.

 Wi th the chi sel fli ppe d over on its back, start a par ing cut. Atfirst, the direction of cut is determined entirely by where you

point the tool. As the cutting edge slices into the wood, it-

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evelops a flat surface behind the cut. The back of the chiselan begin to rest on this surface, which it has itself created, andse the purchase as a guide for ever-increasing accuracy of 

irection. The longer the cut, the more controllable it becomes.f you use this help, you can all but eliminate digging in.

To practice the various techniques we've been discussing, Iwould recommend a short piece of a 1-in, by 2-in. poplar or

mahogany. Using your combination square and a sharp layoutnife, scribe a line around the stick about in. from one end.

Your task is to pare to this line so that you have a nice flat end-rain surface. Figure 2 shows the basic approach, but every piecef wood is different—I won't go so far as to say contrary—sopply the principles in whatever way necessary to suit the job.

Clamp the wood vertically in the vise, sticking up three or fournches above the benchtop. Chamfer the long right-hand edge atoughly 45°. Trying to do this all at once will just get you broken-

ut wood on the other end of the cut—so don't do it. With easy 

Chamfering is the first step in paring a flat end (see drawing).Then bring the surface down in steps, working toward the center.

semi-circular slices, take -in. slices off the corner, aiming

slightly up so that the cutting edge emerges from the woodbefore it gets to the other side. When you're down to your knife

line at the corner, do the same on the other long edge, thenfinish the chamfers as shown in the drawing.

If you're right-handed, the first edge will be the easy one since

 you' ll be able to rest your whole fore fing er on the work. Movingto the left side will require a grip alteration, but a couple of tries

 will help you find a comfortable position. I half-heartedly try todo all operations with either hand. (I say half-heartedly becauseI'm not very good at it—but at least I try.) If you're paring orplaning and run into reverse grain, you can flip the tool into theother direction a lot easier if you're a switch-hitter.

Now turn the work 90° and cut the two short edges. This will

be easier since the following corners are cut down for this step,

too. You now have a chamfer all around the end of the 1x2, rightto your knife line. These can now be cut down flatter with the

same grip and hand action. Slowly work two opposite chamfersdown until you're almost on the flat. Turn the work 90° in the

 vise, and shoot across, square to the cuts you've just made, tofinish off the flattening. If you're having trouble with break-out,rotate the work as many times as you need to, to be able to work

"into" the surface. Finish off with a very light cleanup shave. As you're work ing along an edge, keep in min d that the angle

between the edge of the stock and the cutting edge of the chisel

must be less than 90°, as shown in the drawing. Otherwise, the

outside wood fibers will have a tendency to break away, beingpushed by the chisel without anything backing them up. It canhelp if you imagine the cutting edge and the body of the stock as

two scissor blades, shearing the fibers along the edge.

 When you 're satisfied with the flat end you've produced,scribe a new line, clamp the wood down horizontally on the

bench and chamfer it again. You can either lay the work on apiece of plywood or directly on the surface of the bench, which wil l back up your cuts and prevent break-out, or you can hangthe end out over the end of the bench, a position that more

closely imitates situations you'll encounter in real life. This will

be trickier, but better practice.

Try the other grips (including chin drive) that we've

discussed, and cut the same way you did when the piece was

 vert ical . The more you practi ce and the har der you make it for

 you rse lf (say, cut th e end of the stock on a 120° bevel instead

of square), the quicker and more accurate you'll be when it

really counts.

 Michael Podmaniczky is a contributing editor to FWW.